Alternatives to Customer.io
Other Email marketing vendors we measure, sorted by how much they publish that Customer.io does not. This is a comparison of disclosure, not of features or fitness.
12 shown of 20 that differ from Customer.io on at least one criterion we measured for both. Public transparency score, not a product or security rating.
Customer.io has 3 gaps in what we could measure: Uptime SLA with a figure, No third-party tracking before consent, security.txt (RFC 9116). The column “publishes and Customer.io does not” is the one that closes them.
| Vendor | Score | Publishes, and Customer.io does not | Customer.io publishes, and they do not | |
|---|---|---|---|---|
| Mailgunmailgun.com | 83/100 | 2 Uptime SLA with a figure, No third-party tracking before consent | 1 Subprocessor list | Compare |
| CleverReachcleverreach.com | 48/100 | 2 No third-party tracking before consent, security.txt (RFC 9116) | 4 Data processing agreement, Subprocessor list, Certifications named, +1 | Compare |
| ActiveCampaignactivecampaign.com | 78/100 | 1 Uptime SLA with a figure | 1 Public pricing | Compare |
| Mailchimpmailchimp.com | 57/100 | 1 security.txt (RFC 9116) | 3 Status page with history, Certifications named, HTTPS enforced with HSTS | Compare |
| Omnisendomnisend.com | 57/100 | 1 security.txt (RFC 9116) | 3 Subprocessor list, Data location stated, Certifications named | Compare |
| Campaign Monitorcampaignmonitor.com | 17/100 | 1 security.txt (RFC 9116) | 5 Data processing agreement, Subprocessor list, Data location stated, +2 | Compare |
| Klaviyoklaviyo.com | 65/100 | nothing we found there and not here | 1 Data location stated | Compare |
| EmailOctopusemailoctopus.com | 43/100 | nothing we found there and not here | 3 Subprocessor list, Status page with history, Certifications named | Compare |
| Substacksubstack.com | 38/100 | nothing we found there and not here | 4 Data processing agreement, Subprocessor list, Public pricing, +1 | Compare |
| Elastic Emailelasticemail.com | 35/100 | nothing we found there and not here | 4 Data processing agreement, Subprocessor list, Certifications named, +1 | Compare |
| Postmarkpostmarkapp.com | 35/100 | nothing we found there and not here | 4 Subprocessor list, Data location stated, Status page with history, +1 | Compare |
| Flodeskflodesk.com | 26/100 | nothing we found there and not here | 5 Data processing agreement, Subprocessor list, Status page with history, +2 | Compare |
Only criteria we could measure for both are counted. Where we could measure one and not the other, the row is silent: that would be a statement about our measurement, not about either vendor. Every single result with its source is on the two profiles.